1. Field of the Invention
The present invention relates to a tightening device adapted to equip an article of footwear, such as a shoe, a boot, or a sandal, adapted in particular, but in a non-limiting manner, to the practice of sports. The invention specifies elements related to elements of the tightening device on which the tightening mechanism itself is fixed.
2. Description of Background and Relevant Information
In the prior art, the arrangement for tightening a shoe or boot is often fixed directly on the upper, in the area of the quarters adapted to be brought closer together. In order that the tightening arrangement can hold the foot properly, the upper must be as flexible as possible. If it is too flexible, the upper can no longer distribute the tightening pressure which can prove painful for the foot. Conversely, a rigid upper makes it possible to properly distribute the tightening pressure, but at the expense of the comfort and holding of the foot, which must be compensated for by the use of an inner liner that fills the space left between the upper and the foot.
The document EP 521 287 describes an internal tightening applied to a mountain walking shoe. The tightening device is more precise than the previous device, because it is closer to the foot. However, this internal tightening, which is obtained by flexible elements, retains the aforementioned disadvantages which result from the use of a flexible structure.
The document FR 2 694 167 describes an external tightening device for a mountain hiking boot which includes a rigid flap positioned on the lateral portion, in the area of the instep, on the outer side of the boot. This flap makes it possible to maintain the foot applied against the medial side of the boot upper, due to the tightening arrangement.
However, this device has a discontinuity between the upper end of the rigid flap and the most flexible upper located on the other lateral portion of the foot. This discontinuity, on the top of the instep, can prove very painful for the user, because the tightening device does not make it possible to distribute the tightening pressure. Indeed, the tightening system is anchored directly on the end of the rigid flap.
The document DE 42 29 036 describes a mountain hiking boot in which the two quarters of the upper have an area of overlapping, in particular in the area of the instep, and are provided with a lace tightening system. This device makes it possible to simplify the opening of the boot while ensuring that the latter is impervious. However, the upper does not make it possible to distribute the tightening pressure comfortably on the foot, since it has a substantially identical flexibility on the two quarters. Moreover, the two quarters of the upper deform substantially in a symmetrical manner to encircle the foot, and the tightening device therefore does not apply the foot against a predetermined quarter of the upper.